A tiger of a mosquito: Summer heat rain bring mosquitoes to Buncombe

For those living in Western North Carolina, mosquito bites are a fact of life during summer. These bloodsuckers can be something more than a nuisance, though, as invasive mosquitoes take wing in Buncombe County, transmitting a serious virus known as La Crosse encephalitis. And thanks to the increase in rainfall this year — leading to wet, saturated conditions perfect for mosquito breeding — the community may need to take extra precautions to avoid them, say local health officials.

Haywood, Jackson and Swain counties have typically been hotspots for the La Crosse virus, according to research by Brian Byrd, a Western Carolina University assistant professor and public health biologist. However, in a recent interview with The Western Carolina Journalist, he noted that Buncombe County had seen in an increase in reported cases over the years as well. Buncombe County’s Disease Control Lead Nurse Sue Ellen Morrison confirms there has been an increase of about two cases per year since 2010, with a total of 13 infections reported in 2012.

No encephalitis cases have been recorded this year, according to Morrison, though the mosquitos don’t come out in full force until summer. Once a case has been confirmed through lab tests, a physician’s report is sent to the Department of Health and Human Services. Patients who think they may have the virus are urged by the federal Centers for Disease Control and Prevention to seek medical treatment immediately.

Mild symptoms can include vomiting, fever and lethargy, according to the CDC. Severe cases, commonly found in children younger than 16, include seizures, partial paralysis and, in very rare cases, death.

The virus was first discovered in the 1960s in the town of La Crosse, Wis., where it got its name. Since then, it's made its way across the Midwest and into the Southeast. In WNC, Bryd explains, the virus is primarily transmitted by two nonnative mosquitoes: Aedes albopictus (the Asian Tiger Mosquito) and Aedes japonicas (the Asian rock-pool mosquito). Both mosquitoes thrive in standing water and can be found in residential areas — and neither is very nice. Asian tiger mosquitoes are a particularly aggressive breed. “Those are the ones that'll chase you down the hall,” says Byrd.

With all that in mind, Morrison encourages hikers to wear light-colored long clothing to help protect themselves from bites. She also recommends sprays containing permethrin, which can be applied to clothing and lasts through multiple washes. For a natural alternative, oil of lemon eucalyptus works as a repellent too.

Mosquitoes tend to lay their eggs in still water. This means outside toys, pools and pool covers can be perfect breeding grounds for them. Morrison suggests drilling holes in tire swings and minimizing standing water so that a backyard does not become a happy home for mosquitoes.

So break out the Citronella candles, bug spray and bite ointments — the summer vampires have arrived. Says Morrison, “If we're gonna be outside, we need to protect ourselves from being on their menu.”

For more information on La Crosse encephalitis, visit cdc.gov/lac.

— Brandy Carl is an Xpress news intern and a senior at Western Carolina University. She can be reached at brandy@mountainx.com or 251-1333, ext. 128.